Generally, the backlight module of the existing all-in-one machine of the liquid crystal display includes a light guide plate, a light source, a back cover and a heat dissipation plate. The light guide plate is arranged on the back cover, the heat dissipation plate is arranged between the light guide plate and the back cover and the light source is arranged at the side edge of the light guide plate The circuit board of the light source of at least one side edge of the light guide plate is fixed with heat dissipating fins, and such heat dissipating fins are fixed on the back cover through an elastic component; or the heat dissipating fins are fixed on the back cover through the heat conduction glue after being bent and molded by the aluminum sheets of high thermal conductivity.
In the structure, the LED (Light Emitting Diode) Light-Bar can be selected as the light source, and the aluminum extrusion can be selected as the heat dissipating fin. Generally, the LED Light-Bar is locked onto the aluminum extrusion, and then the aluminum extrusion is assembled on the back cover for processing heat dissipation. However, such structure has the following defects.
1. Since the effective heat-dissipation area contacted between the aluminum extrusion and the back cover is smaller, the heat-dissipation effect of the backlight module would be influenced;
2. Contacts among the interfaces are existed many times during the heat-dissipation ways from the light source to the aluminum extrusion and to the back cover; as a result, the thermal contact resistance becomes larger which further influences the heat-dissipation effect of the backlight module.